Question

Problema de Química fórmula molecular.

Answer 1

P= 250 mmHg /760 = 0.328 atm

T= 300 + 273 = 573 K

D = 0.617 g/l

Datos del CO2

P = 738 / 760 = 0.971 atm

T = 25 + 273 = 298 K

V = 11.4 L

Masa de agua = 8.18 g

Mm = 18 g/mol

CALCULAR MOL DE CARBONO.
P V = n R T

n(mol) =      0.971 atm  x 11.4 L
                `````````````````````````````````
               0.082 (atmL/mol K) 298K

mol = 0.4245 mol CO2 = 0.4245 mol C

mol H2O = 8.18 g x 1 mol  x 2 mol H
                               ``````````  ````````````
                                 18 g      1 mol

mol H2O = 0.9088 = 0.9088 mol H

CALCULAR GRAMOS DE:
CARBONO:
g C = 0.4245 mol C x 12 g C
                                   ``````````
                                   1 mol C
g C = 5.094

g H: 0.9088 mol x  1 g H
                             ````````
                             1 mol H

g H= 0.9088 g

calcular gramos de oxigeno

g O = (10 - 5.094 - 0.9088)g = 3.997 g O

g O = 3.997 g x  1 mol O
                          ``````````
                         16  g O
g O = 0.2498

dividir cada elemento entre el menor de los resultados

C: 0.4245 / 0.2498 = 2
H: 0.9088 / 0.2498 = 4
O: 0.2498/0.2498 = 1

FE: C2H4O

calcular masa molecular de la formula empirica:
C: 2 X 12 = 24 g/mol
H: 4 x1 = 4 g/mol
O: 1 x 16 = 16 g/mol
````````````````````````````
  Mm FE = 44 g/mol

SE TRABAJA CON LA DENSIDAD PARA CALCULAR LA MASA MOLECULAR Y OBTENER LA MASA MOLECULAR DEL COMPUESTO

P = d x R x T
     ``````````````
          Mm

Mm = 0.617 g/L x 0.0821(atm L/mol K) x 573 K
         ````````````````````````````````````````````````````````
                               0.328 atm

Mm = 88 g/mol

n= 88 g/mol / 44 g/mol

n = 2

FM = (C2H4O)2 = C2H8O2